Electric fuse



Jan. ll 1927.

1'.V E. MURRAY ELECTRIC FUSE Filed Jan. 8, l925 lffrrrl Zw. F l l I l l.

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*45 top 5 of the casing has a pair o 55 the arrangement Patented am. 11, 1927. y

UNITI-:O STATES PATENT OFFICE.

:moms it murmur, or BROOKLYN, NEW YORK.

ELECTRIC FUSE.

` Application llled January The present invention covers an improve-` ment on fuses of this type and certain features of improvement applicable to other typesas well. 'l he accompanying drawings 'l5 illustrate an embodiment of the invention.

Fig. 1 is a perspective view of a number of fuses alongside of each other in a casing, the casing being in section on the line 1.-1 of Fig.- 2;

Fig. 2 is a vertical `section between a pair of the fuses;

Fig. 3 isa cross-section of part of a fuse; Fig. 4 is a plan of a fuse; Fig. 5 is a longitudinal section ol'ia fusc of another style;

Fig. 6 is a cross-section thereof on the line (-6;

A F ig: 7 is a verticall section ofa modification. i

vReferring to the embodiment of the invention illustrated, each fuse comprises a f strip 1 in two arms extending along opposite sides of a barrier 2 of perce ain or similar insulating material. lThis strip extends con? 25 tinuously over the top of the barrier where it is provided with a localized blowing point formed, for example, by `a reduced portion f3. The barrier is part of or is mounted inv a casing having a base 4, a top 5 and sides 6 and lpreferably also having end closures. 'lhe top and the ends are omitted from Fig. 1 for the sake of clearness.

Within the casing shown are a ofA similar fuses located side by side. 'lhe t ribs ,7`bearing on the encased upper ends of the fused strips and formingacliamber 8 within which will be confined the gases generated atl the blowing point. There .are thus provided Itwo A means 'for causing a violent separation of the arms of any fuse which blows. First', the gases confined in the chamber 8 and between thel ends of the casings 9 will blow such ends apart. Secondly,

posite sides of the barrier 2 will throw them number the repulsion e'ectdue to A of the branches on' the op.

8.1925. serial no. 1,144,

apart. When any fuse blows, therefore, its partsV will be thrown down t0 the position shown 1n dotted lines at 10, Fig. 1.

Eaclrof the armsof a fuse strip is enclosed in a separate casing consisting ol a liber tube 9 filled with granular material 11.

Fig. 3, this tube extending to and vover the top of the barrier 2 and serving to extin guish any arc which tends to form between the ends of the blown fuse or to prevent such an are from traveling back very far alon f the arms of the fuse strip. The encase larms of the 'fuse strip are arranged to yield very readily at their lower ends. Line terminals' 12 are' provided having Alooped portions 13 set in sockets in the base of the casing so that the ends 14 of the fuse stripmay be forced therein with a good frictional contact. When a fuse is blown and its arms thrown down, the ends 14 will bend or slip with comparative ease out of the looped terminals.

l propose also to providenieans for positively extinguishin the arc by applying to it a quenching flui In' Fig. 2, I have illus trated a container in the form of a sealed glass tube 15 with itsl lower end resting on the ends of the casings 9, being carried in a tubular recess formed by the flanges 7 and opened to the outside of the casing by means of a screw cap 16 to permit insertion and lremoval of the container. This container may be a thin vessel of glass or other frangible or destructible material carrying an arce'xtinguishing material. uy usual'or suitable quenching liquid or gas or solid may be used; specifically carbon tetrachloride, for

example. lVhen there is a blow-out the vessel will be broken and the extinguishing material will be showered upon the arc so as to cti-operate with the other agencies referred to in extinguishing it promptly. l

The same idea may be applied to a great variety of fuses Figs. 5 and 6 show it applied to a fuse of the type illustrated in a (3opending application of mine Serial No. 7 55,135 filed December 11, 1924. In this case the iwo halves ofthe fuse strip 2 are encased at their ends in heads 17 which act in the manner kof pistons in the tubular casing" 18, being thrown apart violently by the gases generated in a space between their. by the blowing out o f the fuse at the point 3. A vessel 19 carrying the 'quenching materialvis arranged in recesses in the two heads so that it extends across the intermediate space and it will be showered down on the are.

Fig. 7 shows the vessel 15 with its lower end having portions 20 in thepath of flanges 2l on the fuse casings 9. lVhen the fuse blows and the casings 9 are forcibl thrown outward, the flanges 21 willpositlvelyf engage and break the bottom of the vessel and release the extinguishing liquid on the arc.

j Though I have described with great particularity of detail a certain embodiment of my invention, yet it is not to be understood therefrom that the invention is restricted to the particular embodiment disclosed. Various modifications thereof may be made by vthose skilled in the art without departing from the invention as defined in the following claims.

What I claim is:

1. An electric fuse comprising a fusel stri with two arms between which is a localize blowing point, casings for said arms extending to points closely adjacent to said blowing point at opposite sides thereof, and means for confining the gases generated by the blowing of the fuse so as to cause a violent separation ofthe two casings.

2. An electric fuse comprising a fuse strip with two arms between which 1s a localized blowing point, casings for said arms extending to points closely adjacent to said blowing point at opposite `s ides thereof, and an g. pulsion e ect between insulating barrier on o posite sides of which said Casin 'are locate so as to induce a rethem and to throw themiapart when the fuse blows.

3. An electric fuse comprising a fuse stri with two arms between which 1s a localize blowing point, casings for said arms extending point at opposite sides thereof, said arms havmg free ends extending beyond said casings and adapted for frictional engagement with circuit terminals.

4. An electric fuse comprising a fuse strip with two arms between which is a localized blowing point^l casings for said arms extending to points closely adjacent to said blowing point so as to confine the arc Lto the space between1 said casings and a body of quenchingV material adapted to extinguish the arc between said casings 5. An electric-'fuse comprising a fuse with t-wo arms between which 1s a localized blowing point, casings for said arms extending to points closely adjacent to said blowing point solas to confine the arc to the space between said casings and a body of quenching material adapted to extinguish the arc between said casings and means for causing a violent separation of said casings when the arc blows.l x

y6. An electric fuse comprising a fuse strip with two arms between which is a localized blowing point in combination with an outside casing carrying the fuse, a vessel carrylmg quenching material, said casing including a chamber for said vessel adjacent to said point, which chamber is open to the outsidel of the casin and means Yfor holding the vessel in said c amber.

In witness whereof, I have hereunto signed my name.

THOMAS E. MURRAY ing topoints closely adjacent to said blowstripv 

